A hydraulically damping bush bearing of this type is known from DE 103 59 340 A1 and also has a pair of axial chambers with at least two axial chambers arranged offset from one another in the axial direction of the inner part and communicating with one another via at least one axial chamber channel. Moreover, a pair of radial chambers with at least two radial chambers, communicating via at least one radial damping channel, which are arranged between the axial chambers and offset in the circumferential direction of the inner part, is provided. The damping part is longitudinal, configured typically as a cylinder. In generic bush bearings, the inner part generally has a hole for receiving an axle pin of a machine element or component to be mounted.
Generic hydraulically damping bush bearings are used mainly in automotive engineering to mount parts of the wheel suspension or drive assemblies of vehicles. In addition to elastic damping elements, which are typically made from an elastomer, the hydraulically damping bush bearing comprises chambers for receiving a hydraulic damping fluid that supports damping. To utilise the dissipating effect caused by the weight of liquid, chambers are provided in the elastomeric insert parts or rubber bodies of the hydraulically damping bush bearings to receive a fluid damping agent. The exact size and position of the chambers depends on the intended use of the hydraulically damping bearing, more particularly the respective desired dissipating effects in an axial, i.e. longitudinal direction of the inner part and a direction at right angles thereto, i.e. radial direction. The oscillation characteristics of the component to be mounted are also important as well as the dead weight of the damping mass to be mounted. In any case, the chambers are typically interconnected by one or more channels. Depending on the stress on the bearing, the hydraulic damping agent can thus be pressed from one chamber into another. Both bearings in which the hydraulic damping is used in respect to forces introduced radially into the bush bearing and bearings in which mainly the damping is supported by the damping fluid are known in this connection. The prior art referred to above is evidence of a bush bearing in which the amortizing effect is utilised in both an axial and a radial direction.
It has been shown, however, that when generic hydraulically damping bush bearings are exposed to higher frequency oscillations, more particularly oscillations ranging between 50 Hz and 150 Hz, in particular >250 Hz, of the component to be mounted in a damping manner, unintentionally high damping occurs and thus hardening. The required damping by means of the hydraulically damping bush bearing is no longer guaranteed in the desired manner at said higher frequencies.